1. Technical Field
The present invention relates to a grommet and a water stop structure for a vehicle door using the grommet.
2. Background Art
Conventionally, as a water stop (waterproofing) structure for a door harness cabled on a vehicle door, a waterproofing structure has been known in which a through hole and a concave portion for a grommet are provided on an end surface (side plate) of a door frame hinge-connected to the vehicle body, the grommet attached to the door harness is fitted in the through hole and the door harness is cabled from the door to the vehicle body. In addition, various technologies have been proposed for the improvement of the waterproofing structure and the improvement of workability.
For example, a technology is available where in a grommet to which a protector is attachable, by making changeable the diameter of the through hole through which the wire harness is passed at the protector, a multiplicity of wire harness diameters are handled by combining parts of one kind (see JP-A-2005-349984).
In a grommet of non-through type being attached to the vehicle body by a resin clamp, a structure called a water stop lip is formed along the outer periphery of the grommet. Such a structure is illustrated in FIG. 11A to FIG. 11C. FIG. 11A is a plan view, FIG. 11B is a XIB-XIB cross-sectional view of FIG. 11A, and FIG. 11C is a plan view schematically showing the disposition of a water stop lip 132 and a weather strip 90 of FIG. 11A.
As illustrated, a grommet 110 is provided with a grommet base portion 120 and a bellows portion 140. The grommet 110 has a protector 170 secured to its back surface portion (inner surface portion) 124, and is attached to a grommet concave portion 152 of a door panel 150 (a side plate part A2). On the back surface portion 124 of the grommet base portion 120, the water stop lip 132 is formed along the outer periphery. When the grommet 110 is attached to the grommet concave portion 152, the water stop lip 132 is pressed against a slanting wall portion 153 of the grommet concave portion 152 so as to be deformed, thereby preventing the water intrusion from the outside to the inside of the grommet 110.
In the grommet 110 of the structure shown in FIG. 11, since the water stop lip 132 is formed along the outer periphery of the grommet base portion 120, the peripheral length of the grommet 110 and the length of the water stop lip 132 are substantially similar. That is, a relatively long water stop lip 132 is required. Consequently, the insertion load in attaching the grommet 110 to the grommet concave portion 152 is heavy, so that a countermeasure technology is required from the viewpoint of workability. Moreover, since the water stop lip 132 abuts on the slanting wall portion 153, there are cases where the grommet 110 is attached in a state of being shifted in a horizontal direction with respect to the attachment surface due to the tolerance of a hole provided in the grommet concave portion 152 to lock a clamp portion 171, that is, the tolerance of the body panel, or the like. In this case, there is a worry that there are variations in the wrap amount of the water stop lip 132 and water stopping performance cannot be maintained, so that a different technology is required. The technology disclosed in JP-A-2005-349984 which adopts a similar structure has a similar problem.